An automated data acquisition system for the Vacuum Generators HB 501 ultrahigh-resolution dedicated scanning transmission electron microscope is being developed. The new analytical capabilities of this class of electron microscope require fresh approaches to computerization of data acquisition and analysis and it is for this reason that we were required to construct our own system rather than assemble commercial products. The completed and nearly completed components of the data acquisition system obtain x-ray spectra from the microscope and perform a wide range of mathematical and physical procedures to extract chemical information concerning the specimen under observation. The system is comprised of a Macintosh II computer with several National Instruments interface plug-in bus cards and an extensive computer program that uses Macintosh and National Instrument routines to control the Macintosh-user interface and the cards. Components of the acquisition system are under active development, but some months away from completion are the bright and dark field imaging and the electron energy loss modes.